DESCRIPTION The btrace script provides a quick and easy
way to do live tracing of block devices. It calls blktrace
on the specified devices and pipes the output through
blkparse for formatting. See blktrace (8) for more in-depth
information about how blktrace works.

OPTIONS -s Displays data sorted by program (see blkparse
(1)).

-t Displays time deltas per IO (see blkparse (1)).

-w N Sets run time to the number of seconds specified
(see blktrace (8)).